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1.
L. Dvorakova J. Sikora M. Hrebicek H. Hulkova M. Bouckova L. Stolnaja M. Elleder 《Journal of inherited metabolic disease》2006,29(4):591
Summary We present the third case of Niemann–Pick disease type C without neurological symptoms. The patient was a 53-year-old woman
without significant prior health problems who died of acute pulmonary embolism. Autopsy findings of hepatosplenomegaly, lymphadenopathy
and ceroid-rich foam cells raised the suspicion of the visceral form of acid sphingomyelinase deficiency (Niemann–Pick disease
type B; NPB) or a much rarer disorder, variant adult visceral form of Niemann–Pick disease type C (NPC). To verify the histopathological
findings, SMPD1, NPC1 and NPC2 genes were analysed. Two novel sequence variants, c.1997G>A (S666N) and c.2882A>G (N961S) were detected in the NPC1 gene. No pathogenic sequence variants were found either in the SMPD1 gene mutated in NPB or in NPC2 gene. The pathogenicity of both NPC1 variants was supported by their location in regions important for the protein function. Both variations were not found in
more than 300 control alleles. Identified sequence variations confirm the diagnosis of the extremely rare adult visceral form
of Niemann–Pick disease type C, which is otherwise dominated by neurovisceral symptoms. Although only three patients have
been reported, this (most probably underdiagnosed) form of NPC should be considered in differential diagnosis of isolated
hepatosplenomegaly with foam cells in adulthood.
Electronic supplementary material Supplementary material is available for this article at 相似文献
2.
Palat Balachandran M.S. M.Ch. Shaleen Agarwal M.S. M.Ch. Narendra Krishnani M.D. Chandra M. Pandey Ph.D. Ashok Kumar M.S. M.Ch. Sadiq S. Sikora M.S. Rajan Saxena M.S. Vinay K. Kapoor M.S. 《Journal of gastrointestinal surgery》2006,10(6):848-854
The aim of this study was to examine the predictors of long-term survival (>24 months) in patients with gall bladder cancer.
A retrospective review of 117 cases of gall bladder cancer resected between 1989 and 2000. The resections included 80 simple
cholecystectomies and 37 extended procedures. Patients with survival >24 months (n=44) were compared with those having survival
<24 months (n=73) for 17 prognostic factors. Overall median survival was 16 months with a 5-year survival of 27%. T status
(P=.000) and adjuvant chemoradiotherapy (P=.001) were independent predictors of long-term survival. Survival advantage was
seen in T3N+ve disease (P=.007) with extended procedures. Complete (R0) resection was attained in 30 patients with a 5-year
survival advantage of 30% as compared with incomplete (R1) resection (P=.0002). Adjuvant chemoradiotherapy improved survival
in simple cholecystectomy group (P=.0008) but no advantage was seen after extended procedures. Stage III (P=.001) and node-positive
disease (P=.0005) had significant benefit with adjuvant therapy. Poor differentiation and vascular invasion were associated
with poor long-term survival. R0 resection was associated with prolonged survival. Extended procedures improved survival in
patients with T3N+ve disease. Addition of chemoradiotherapy made significant improvement in long-term survival in stage III
and node-positive lesions and in patients undergoing simple cholecystectomy. R0 resection predicted long-term survival in
gall bladder cancer. T3 N+ve disease had better survival after extended procedures. Adjuvant chemoradiotherapy improved survival
in stage III and node-positive disease. Poor differentiation and vascular invasion were adverse predictors of survival. 相似文献
3.
Tim Wagner Jarrett Rushmore Antoni Valero-Cabre 《Cortex; a journal devoted to the study of the nervous system and behavior》2009,45(9):1025-137
Transcranial Magnetic Stimulation (TMS) induces electrical currents in the brain to stimulate neural tissue. This article reviews our present understanding of TMS methodology, focusing on its biophysical foundations. We concentrate on how the laws of electromagnetic induction apply to TMS; addressing issues such as the location, area (i.e., focality), depth, and mechanism of TMS. We also present a review of the present limitations and future potential of the technique. 相似文献
4.
5.
Laura Cisneros Maria-Carlota Londo?o Carmen Blasco Ramón Bataller Rosa Miquel Miquel Bruguera Pere Ginès Antoni Rimola 《Liver transplantation》2007,13(7):1017-1027
The pathogenic mechanisms of accelerated graft fibrosis in hepatitis C recurrence after liver transplantation (LT) are not well established. The aim of the study was to assess whether a greater activation of hepatic stellate cells (HSC), the major collagen-producing cells in the liver, can occur in these patients as compared to non-LT patients with chronic hepatitis C. We determined the amount of activated HSC by computer-based morphometric analysis of alpha-smooth muscle actin (alphaSMA)-positive cells and the hepatic TGFbeta(1) expression by immunohistochemistry in 46 LT patients with hepatitis C recurrence, 35 non-LT patients with chronic hepatitis C, and 16 controls. Hepatic alphaSMA and TGFbeta(1) expression was higher in LT patients with hepatitis C recurrence than in controls and was correlated with fibrosis stage and progression rate. No significant difference in alphaSMA and TGFbeta(1) expression was observed between LT and non-LT patients with hepatitis C, with the exception of a higher transforming growth factor beta-1 (TGFbeta(1)) expression in non-LT patients in the early stages of fibrosis. LT patients receiving cyclosporine (CsA) or tacrolimus (FK) had a similar fibrosis progression rate and alphaSMA and TGFbeta(1) expression. In conclusion, the accelerated fibrosis observed in LT patients with hepatitis C recurrence does not seem to be related to a greater amount of activated HSC and TGFbeta(1) expression in the grafts of these patients as compared to non-LT patients with chronic hepatitis C. In LT patients, the amount of activated HSC and TGFbeta(1) expression correlated with fibrosis stage and progression, without any apparent influence of the type of calcineurin inhibitor administered. 相似文献
6.
7.
Y. Tani T. Ishihara T. Kanai T. Ohno J. Andersson A. Lilja G. Antoni K. -J. Fasth P. Bjurling G. Westerberg P. Hartvig H. Onoe Y. Watanabe B. Langström 《Journal of neural transmission (Vienna, Austria : 1996)》1995,102(3):189-208
Summary The effects of 6R-L-erythro-5,6,7,8-tetrahydrobiopterin (R-THBP) on the central cholinergic and dopaminergic systems in the Rhesus monkey brain were investigated by positron emission tomography (PET) with the muscarinic cholinergic receptor ligands (N-[11C]methyl-benztropine) and dopaminergic receptor ligands selective for D1 D2, and D3 subtypes ([11C]SCH23390, N-[11C]methyl-spiperone, and (+)[11C]UH232, respectively). None of the doses (3, 10, and 30 mg/kg i.v.) of R-THBP used significantly affected the regional cerebral blood flow (rCBF as determined by Raichle's H2
15O method), and 10 mg/kg of R-THBP had little effect on the regional cerebral metabolic rate of glucose (rCMRglc) in the Rhesus monkey brain, as assessed by the graphical [18F]fluoro-deoxyglucose method. The effect of R-THBP on the muscarinic cholinergic system was dose dependent; while 3 mg/kg of R-THBP did not significantly alter the uptake ratio of N-[11C]methyl-benztropine in several brain regions to that in the cerebellum, 10 and 30 mg/kg of R-THBP significantly reduced the uptake ratio in the thalamus, as well as in the frontal and temporal cortices. None of the doses (3, 10, and 30 mg/kg i.v.) of R-THBP tested affected [11C]SCH23390 (dopamine D1 receptor) binding. However, the k3 value for N-[11C]methyl-spiperone (dopamine D2 receptor) binding, which represents the association rate × Bmax value, was significantly decreased in the striatum. The uptake ratio of (+)[11C]UH232 (dopamine D3 receptor) in the striatum to that in the cerebellum was also decreased by administration of R-THBP (3 and 30 mg/kg i.v.). These findings suggest that R-THBP acts on dopamine D2 and D3 receptors selectively without markedly affecting dopamine D1 receptor binding. Furthermore, the changes in cholinergic and dopamine D2 and D3 receptors in vivo can not be attributed to a change in rCBF but may depend on the action of R-THBP.Abbreviations
R-THBP
6R-L-erythro-5,6,7,8-tetrahydrobiopterin
-
PET
positron emission tomography
-
rCBF
regional cerebral blood flow
-
rCMRglc
regional cerebral metabolic rate of glucose 相似文献
8.
The frequency-dependent block of cardiac sodium channels by class 1 antiarrhythmic drugs can be described by a periodical ligand binding process between drug molecules and channel binding sites. This predicts a linear relation between onset-rate constant of frequency-dependent block and diastolic interval as well as saturation of block with high stimulation rates. From both relationships, the binding kinetics (time constant, tau on) and saturation level of block (bdinf) can be estimated. This is exemplified for the frequency-dependent block (reduction of the maximal upstroke velocity of action potentials) induced by prajmaline (10(-6) M). In the same way, the frequency-dependent effects of 11 other class 1 drugs reported in the literature were analyzed and compared with each other. When the drugs are ranked with respect to their binding kinetics (tau on), there is a close relationship to the subclasses (1a, 1b, 1c), with 1b drugs exhibiting the fastest and 1c drugs the slowest kinetics. However, differences also exist in the saturation behavior of frequency-dependent block even within the same subclasses (1a and 1c). Thus, the class 1 drugs can also be subdivided in three other groups exhibiting clearly separated bands of block-frequency relations, with half-maximal saturation occurring at different stimulation rates. Our findings may have differential implications for the antiarrhythmic and proarrhythmic efficacy of class 1 drugs. 相似文献
9.
Wasif Ali Deepak K. Agarwal Sadiq S. Sikora Bhagwant R. Mittal Narendra Krishnani Md. Ibrarullah Ramesh K. Gupta Satyendra P. Kaushik 《Surgery today》1997,27(3):247-250
Duodenogastric reflux (DGR) has been implicated in several disease processes. The present study was carried out to document the incidence and evaluate the clinical significance of DGR after choledochoduodenostomy (CDD). A total of 13 patients who had undergone cholecystectomy with a standard side-to-side CDD for choledocholithiasis or chronic pancreatitis were studied by symptom evaluation, scintigraphy, endoscopy, and gastric mucosal histology at least 6 months after surgery. The scintigraphic findings were then compared with those of 10 patients who had undergone cholecystectomy alone. Only two patients (15%) had mild dyspeptic symptoms. The incidence of DGR after CDD was 69% compared to 20% in the cholecystectomy alone group (P < 0.05). In the majority of patients the DGR was only mild to moderate and the severity correlated well with the degree of endoscopic gastritis, but not with the clinical symptoms or histological findings. These results indicate that while CDD is associated with a high incidence of DGR, its occurrence does not produce significant clinical symptoms. 相似文献
10.
Wladyslaw Mielczarski Antoni M. Zajaczkowski 《Optimal control applications & methods.》1994,15(1):49-65
The problem of multivariable controller synthesis for a turbogenerator is considered. Using the feedback linearization approach for multi-input non-linear systems, the existence of a linearizing state feedback for the improved reduced-order model of a turbogenerator is proved and the simplest form of this feedback is derived. Application of the obtained non-linear controller to the multivariable control of a turbogenerator provides very good results not only for the reduced-order model but also for the ‘exact’ (Park's) model of a turbogenerator. Simulations of fault and post-fault conditions in the obtained nonlinear control system confirm its superiority over a system with a voltage regulator and power system stabilizer. 相似文献